Question

What id the circumference of the circle? use 22/7 for pi, r=21 cm

Analytic geometry
What id the circumference of the circle? use $$\displaystyle\frac{{22}}{{7}}$$ for $$\displaystyle\pi,{r}={21}$$ cm

2021-01-23

Similar to circle sphere is a two dimensional space where the set of points that are at the same distance r from a given point in a three dimensional space. In analytical geometry with a center and radius is the locus of all points is called sphere.
Circumference:
The distance around a circle is called its circumference.The circumference of the circle is $$\displaystyle{C}={2}\pi{r}$$
Taking $$\displaystyle\pi\stackrel{\sim}{=}{\frac{{{\left\lbrace{22}\right\rbrace}}}{{{\left\lbrace{7}\right\rbrace}}}}$$
The object is to find the circumference for the given circle as follows. The radius of the circle is r=21
Then the circumference of the circle is,
$$\displaystyle{C}={2}\pi{r}$$
$$\displaystyle{C}={2}{\left(\frac{{22}}{{7}}\right)}{\left({21}\right)}$$
C=132 cm.
So the circumference of the circle is approximately 132 cm.